Also known as ScyllaDB
ScyllaDB is a source-available distributed NoSQL wide-column data store. It was designed to be compatible with Apache Cassandra while achieving significantly higher throughputs and lower latencies. It supports the same protocols as Cassandra (CQL) and the same file formats (SSTable), but is a completely rewritten implementation, using the C++20 language replacing Cassandra's Java, and the Seastar asynchronous programming library replacing classic Linux programming techniques such as threads, shared memory and mapped files. In addition to implementing Cassandra's protocols, ScyllaDB also implem
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ScyllaDB is a source-available distributed NoSQL wide-column data store. It was designed to be compatible with Apache Cassandra while achieving significantly higher throughputs and lower latencies. It supports the same protocols as Cassandra (CQL) and the same file formats (SSTable), but is a completely rewritten implementation, using the C++20 language replacing Cassandra's Java, and the Seastar asynchronous programming library replacing classic Linux programming techniques such as threads, shared memory and mapped files. In addition to implementing Cassandra's protocols, ScyllaDB also implements the Amazon DynamoDB API.
ScyllaDB uses a sharded design on each node, meaning that each CPU core handles a different subset of data. Cores do not share data, but rather communicate explicitly when they need to. The ScyllaDB authors claim that this design allows ScyllaDB to achieve much better performance on modern NUMA SMP machines, and to scale very well with the number of cores. They have measured as much as 2 million requests per second on a single machine, and also claim that a ScyllaDB cluster can serve as many requests as a Cassandra cluster 10 times its size – and do so with lower latencies. Independent testing has not always been able to confirm such 10-fold throughput improvements, and sometimes measured smaller speedups, such as 2x. A 2017 benchmark from Samsung observed the 10x speedup on high-end machines – the Samsung benchmark reported that ScyllaDB outperformed Cassandra on a cluster of 24-core machines by a margin of 10–37x depending on the YCSB workload.
Scylla is the real-time big data database that is API-compatible with Apache Cassandra and Amazon DynamoDB. Scylla embraces a shared-nothing approach that increases throughput and storage capacity to realize order-of-magnitude performance improvements and reduce hardware costs. Scylla is fairly fussy about its build environment, requiring very recent versions of the C++23 compiler and of many libraries to build. The document HACKING.md includes detailed information on building and developing Scylla, but to get Scylla building quickly on (almost) any build machine, Scylla offers a frozen toolchain. This is a pre-configured Docker image which includes recent versions of all the required compilers, libraries and build tools. Using the frozen toolchain allows you to avoid changing anything in your build machine to meet Scylla's requirements - you just need to meet the frozen toolchain's prerequisites (mostly, Docker or Podman being available). [Developer documentation] for more information on building Scylla. [Build documentation] on how to build Scylla binaries, tests, and packages. [Docker image build documentation] for information on how to build Docker images. This will start a Scylla node with one CPU core allocated to it and data files stored in the tmp directory. The --developer-mode is needed to disable the various checks Scylla performs at startup to ensure the machine is configured for maximum performance (not relevant on development workstations). Please note that you need to run Scylla with dbuild if you built it with the frozen toolchain. Scylla APIs and compatibility By default, Scylla is compatible with Apache Cassandra and its API - CQL. There is also support for the API of Amazon DynamoDB™, which needs to be enabled and configured in order to be used. For more information on how to enable the DynamoDB™ API in Scylla, and the current compatibility of this feature as well as Scylla-specific extensions, see Alternator and Getting started with Alternator. Documentation can be found here. Seastar documentation can be found here. User documentation can be found here. Training material and online courses can be found at Scylla University. The courses are free, self-paced and include hands-on examples. They cover a variety of topics including Scylla data modeling, administration, architecture, basic NoSQL concepts, using drivers for application development, Scylla setup, failover, compactions, multi-datacenters and how Scylla integrates with third-party applications. If you are a developer working on Scylla, please read the [developer guidelines]. The [community forum] and [Slack channel] are for users to discuss configuration, management, and operations of ScyllaDB. The [developers mailing list] is for developers and people interested in following the development of ScyllaDB to discuss technical topics.
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